Do I have that spelled right? It's one of the hip stabilizer muscles that lies deep under your intestines, along the inside of your spinal column. I had a deep tissue massage person work on it once and nearly came off the table. But dang, did the pain go away!

And because it's mostly a posture muscle, it's one of those you're not really conscious of.

Larger point: Have you looked at Rolfing, or deep tissue or trigger point work with someone who's REALLY qualified, not just saying "Yeah, I can do that too." I have found these treatments helpful for problems that more conventional medical practitioners don't see.

VERY Useful book: The Anatomy of Movement, by Blandine Calais-Germain. It shows exactly what muscle moves which parts how, and helps me to pinpoint EXACTLY what's hurting, which can be tricky when it's that complicated mess that runs my hips and butt.

Good luck.